JP2013247170A - Changeover switch and on-load tap changer using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance durability by suppressing consumption of a neutral contact, and to enhance positioning accuracy, compactness and economy by simplifying the configuration.SOLUTION: A neutral contact 16, a first tap contact 17 and a second tap contact 18 are provided to surround movable contacts 10, 11. Cam plates 12, 13 are secured to a switching shaft 9. Cam grooves on cam discs 12, 13 are formed so that the radial guide position in the movable contacts 10, 11 changes in reverse phase, when the cam discs 12, 13 rotate. Consequently, when the first cam plate 12 operates the first movable contact 10, and the first movable contact 10 comes into contact with the neutral contact 16 and the first tap contact 17, the second cam plate 13 operates the second movable contact in the reverse direction, thus separating the second movable contact 11 from the neutral contact 16 and the second tap contact 18.

Description

  Embodiments described herein relate generally to a switching switch for switching a transformer tap and a load tap switching device using the same.

  In general, a transformer connected to a power transmission / distribution system incorporates a load tap switching device that adjusts and stabilizes the system voltage. The on-load tap switching device includes a tap selector and a switching switch. The tap selector selects the position of a pair of taps drawn from the tap winding of the transformer.

  The switching switch performs switching of the taps without cutting off the load current by creating a short circuit state via a resistor between a pair of taps selected by the tap selector. For this reason, the switching switch has a mechanism for flowing current only during the tap switching operation. Since current flows through the switching switch even in a steady state, it is necessary to consider connection resistance and heat dissipation. Therefore, in the switching switch of the on-load tap switching device having a large current capacity, in addition to the mechanism for passing a current only during the tap switching operation, an energization switching mechanism that switches between energization of the neutral potential and the pair of tap potentials; An energy storage mechanism is provided that stores the switching power and applies torque to the energization switching mechanism during the switching operation.

  By the way, since the switching switch has a U phase, a V phase, and a W phase, it is desirable that the components of the device are configured uniformly from the viewpoint of timing accuracy and maintainability. Patent documents 1 and 2 etc. are proposed as conventional technology which meets such a need. Specifically, a switching shaft for obtaining torque from the energy storage mechanism is rotatably provided at the center of the energization switching mechanism, and the movable contact is provided for each of the U phase, V phase, and W phase so as to surround the switching shaft. And the fixed contacts are arranged uniformly.

  Among these, the fixed contact is composed of a first and second tap contact having a pair of tap potentials and a neutral contact having a neutral potential. On the other hand, the movable contact is rotatably installed between the two tap contacts. One end of the movable contact is a fixed end that is always connected to the neutral contact, and the other end is a free end that is connected to one of the tap contacts. Further, as a member for transmitting torque from the switching shaft to the movable contact, a cam plate is fixed to the switching shaft, and a link lever that connects the cam plate and the movable contact is provided.

  In the energization switching mechanism having the above-described configuration, when the torque is obtained from the energy storage mechanism and the switching shaft rotates, the cam plate rotates in conjunction with this, and the link lever connected to the cam plate operates to move the movable contact. Rotate. Accordingly, the movable contact rotates with the fixed end connected to the neutral contact as a fulcrum, and the free end is separated from one of the tap contacts and connected to the other tap contact.

  When the switching shaft rotates in the reverse direction, the cam plate, link lever and movable contact operate in the reverse direction, and the other tap is moved away from the tap contact where the free end of the movable contact was connected. Connect with contact. In this way, connection switching between the neutral potential and the pair of tap potentials is performed in the on-load tap switching device.

JP 2010-258266 A JP 2010-80590 A

  In the conventional switching switch, the neutral contact frequently repeats the sliding operation, and there is a problem that the contact is heavily worn. This is because the neutral contact is always in contact with the fixed end of the movable contact. When the neutral contact is worn out, the switching switch is liable to have an excessive temperature rise due to a decrease in contact resistance. As a result, the durability of the switching switch is weakened, and further, the durability of the on-load tap switching device including the switching switch is weakened.

  In addition, when a link lever is interposed between the cam plate fixed to the switching shaft and the movable contact, the amount of movement of the link lever is often different from the amount of movement of the movable contact. For example, the cam plate may control the vertical position of one end of the link lever to move the other end of the link lever in the horizontal direction to position the movable contact in the horizontal direction.

  In this case, the amount of vertical movement at one end of the link lever is usually smaller than the amount of horizontal movement of the movable contact. If the amount of movement of the link lever is different from the amount of movement of the movable contact, the amount of movement of the movable contact is likely to be affected by member dimensions, assembly errors, and the like. Therefore, in the conventional switching switch, it has been a problem to adjust the positioning of the movable contact with high accuracy.

  Further, since the central axis of the link lever turning operation is shifted from the switching shaft, the occupied space including the operation range of the link lever becomes large. For this reason, it is difficult to make the conventional switching switch compact in structure, and the on-load tap switching device is enlarged, which is economically disadvantageous.

  The switching switch according to the present embodiment and the on-load tap switching device using the same are proposed in order to solve the above-described problem, and the movable contact is brought into contact with and separated from both the tap contact and the neutral contact. In this way, the switching contact switch with excellent positioning accuracy, compactness, and economical efficiency, and the tap switching device under load using the same, which improves the durability by suppressing the consumption of the neutral contact and simplifies the configuration. The purpose is to do.

In order to achieve the above object, the switching switch of the present embodiment includes the following (1) to (8).
(1) A first tap contact having a first tap potential.
(2) A second tap contact having a second tap potential.
(3) At least one neutral contact having a neutral potential.
(4) A first movable contact that can be freely contacted and separated from the first tap contact and the neutral contact.
(5) A second movable contact that can freely come in contact with and separate from the second tap contact and the neutral contact.
(6) A rotatable switching shaft.
(7) A first cam plate fixed to the switching shaft and operating the first movable contact.
(8) A second cam plate fixed to the switching shaft and operating the second movable contact.

Sectional drawing of this embodiment. FIG. The perspective view of the fixed contact of this embodiment. The bb cross-sectional perspective view of FIG. The perspective view of the movable contact of this embodiment. The cc cross-section perspective view of FIG.

Hereinafter, the switching switch according to the present embodiment and the on-load tap switching device using the same will be described in detail with reference to FIGS.
(1) Configuration (Overview)
The on-load tap switching device of the present embodiment includes a tap selector that selects the position of a pair of taps drawn from the tap winding, and a switching switch that switches the tap without cutting the load current. The switching switch according to the present embodiment includes an energization switching mechanism for switching energization between a neutral potential and a pair of tap potentials, and an accumulation mechanism that accumulates switching power and applies torque to the energization switching mechanism during a switching operation. And are provided.

  As shown in FIG. 1, a switching shaft 9 that obtains torque from an accumulator mechanism (not shown) is rotatably provided at the center of the energization switching mechanism. Disk-shaped guide plates 14 and 15 are fixed horizontally to the switching shaft 9. In FIG. 1, the guide plate 14 is positioned on the upper side, and the guide plate 15 is positioned on the lower side.

  The first cam disk 12 and the second cam disk 13 are coaxially fixed to the switching shaft 9 so as to be sandwiched between the guide plates 14 and 15. The two cam disks 12, 13 are arranged horizontally and in parallel so as to face each other. In FIG. 1, the first cam disk 12 is positioned on the lower side, and the second cam disk 13 is positioned on the upper side.

  2 is a perspective cross-sectional view taken along the line aa in FIG. 1, and the vertical relationship is reversed from that in FIG. That is, in FIG. 1, the first cam disk 12 is positioned on the lower side and the second cam disk 13 is positioned on the upper side, but in FIG. 2, the first cam disk 12 is positioned on the upper side and the second cam disk 13 is positioned on the lower side. Located on the side. As shown in FIG. 2, along the circumferential portion of the first guide plate 14, a neutral contact 16, a first tap contact 17, and a second tap contact 18 that are fixed contacts are connected to a U phase, a V phase, and a W phase. A total of nine are arranged, three for each phase. The nine fixed contacts include neutral contacts 16a to 16c, first tap contacts 17u, 17v, and 17w, and second tap contacts 18u, 18v, and 18w.

  The first movable contact 10 and the second movable contact 11 are disposed inside these fixed contacts 16, 17, 18. The 1st movable contact 10 and the 2nd movable contact 11 are comprised from the substantially rectangular parallelepiped member, and are arrange | positioned 1 each for every phase of U phase, V phase, and W phase. The 1st movable contact 10 consists of 10a, 10b, 10c, and the 2nd movable contact 11 consists of 11a, 11b, 11c.

(Fixed contact)
The nine fixed contacts 16 to 18 are installed outside the movable contacts 10 and 11 so as to surround the movable contacts 10 and 11. In FIG. 3, the movable contacts 10 and 11, the cam disks 12 and 13, and the guide plate 15 shown in FIG. 2 are omitted, and only the fixed contacts are shown. Note that reference numeral 28 shown in FIG. 3 denotes an insulating cylinder, and 29 denotes a tap contact switching movable contact mechanism disposed on the inner periphery of the insulating cylinder 28. The tap potential switching movable contact mechanism 29 is composed of a substantially triangular base portion that is rotatably supported and electrical contacts provided at each vertex portion of the base portion. The electrical contacts are connected to the first tap contacts 17u, 17v, 17w located on the inner peripheral surface of the insulating cylinder 28 and the junction contacts provided at the ends of the second tap contacts 18u, 18v, 18w, as will be described later. It can be electrically connected and separated. Thereby, the potentials of the first tap contacts 17u, 17v, 17w and the second tap contacts 18u, 18v, 18w are switched.

  As shown in FIG. 3, the neutral contacts 16 a to 16 c, the first tap contacts 17 u, 17 v, 17 w and the second tap contacts 18 u, 18 v, 18 w are all fixed to the guide plate 14. Further, the other end portions of the neutral contacts 16 a to 16 c are fixed along the outer peripheral surface of the insulating cylinder 28. The neutral contacts 16a to 16c, the first tap contacts 17u, 17v, 17w, and the second tap contacts 18u, 18v, 18w are provided to extend in the axial direction of the insulating cylinder 28. The other end portions of the first tap contacts 17u, 17v, 17w and the second tap contacts 18u, 18v, 18w are fixed along the inner peripheral surface of the insulating cylinder 28. The ends of the first tap contacts 17u, 17v, 17w and the second tap contacts 18u, 18v, 18w located on the inner peripheral surface of the insulating cylinder 28 can be used as joint contacts of the tap potential switching movable contact mechanism 29. It is configured.

  The arrangement order of the nine fixed contacts, the neutral contacts 16a to 16c, the first tap contacts 17u, 17v, 17w, and the second tap contacts 18u, 18v, 18w, is as follows. That is, they are arranged in the order of 17u, 18u, 16c, 17v, 18v, 16b, 17w, and 18w in the clockwise direction starting from the neutral contact 16a that faces the movable contacts 10a and 11a.

  Each neutral contact 16 is disposed between the tap contacts 17 and 18. Each neutral contact 16 faces the movable contacts 10 and 11 and is disposed between the movable contacts 10 and 11. For this reason, the neutral contact 16 comes into contact with or separates from the first tap contact 17 through the first movable contact 10 or comes into contact with or separates from the second tap contact 18 through the second movable contact 11. . That is, the neutral contact 16 is configured as a single component by sharing the neutral contact connected to the first tap contact 17 and the neutral contact connected to the second tap contact 18.

(Cam disc)
As shown in FIG. 4, cam grooves 13 a to 13 c having different radial positions in the circumferential direction are formed on the upper surface side of the second cam disk 13. A first movable contact 10 and a second movable contact 11 are provided adjacent to the outer periphery of the second cam disk 13, and one end of the second movable contact 11 is engaged with the cam grooves 13a to 13c. .

  Although not shown in FIG. 4, a cam groove that engages one end of the first movable contact 10 is formed on the lower surface side of the first cam disk 12. The cam grooves of the two cam disks 12 and 13 have the same shape, and are arranged so that the cam grooves face each other, so that the two cam disks 12 and 13 are rotated when the cam disks 12 and 13 are rotated. The upper cam groove is formed so that the change in the radial guide position of the movable contacts 10 and 11 is in the opposite phase.

(Movable contact)
As shown in FIGS. 2 and 4, the first movable contact 10 and the second movable contact 11 are alternately arranged so as to surround the cam disks 12 and 13, and are movable in the radial direction of the cam disks 12 and 13. It is configured. The arrangement order of the first movable contacts 10a, 10b, 10c and the second movable contacts 11a, 11b, 11c is the order of 11a, 10b, 11b, 10c, 11c counterclockwise starting from 10a.

  When the arrangement relationship between the fixed contact and the first movable contact 10 is viewed from the first movable contact 10 side, the neutral contact 16 is arranged close to the left side and close to the right side with respect to the first movable contact 10. The first tap contact 17 is arranged. Therefore, when the first movable contact 10 moves outward in the radial direction, the left edge of the first movable contact 10 contacts the neutral contact 16 and the right edge contacts the first tap contact 18. It has become.

  When the arrangement relationship with the movable contact 11 is viewed from the second movable contact 11 side, the neutral contact 16 is disposed adjacent to the right side and the second tap contact adjacent to the left side with respect to the second movable contact 11. 18 is arranged. Therefore, when the second movable contact 11 moves outward in the radial direction, the right edge of the second movable contact 11 contacts the neutral contact 16 and the left edge contacts the second tap contact 18. It has become.

  The first movable contact 10 and the second movable contact 11 are arranged with the same shape turned upside down. Therefore, the right edge of the first movable contact 10 that contacts and separates from the first tap contact 17 and the left edge of the second movable contact 11 that contacts and separates from the second tap contact 18 are the same edge. Moreover, the left edge part of the 1st movable contact 10 and the right edge part of the 2nd movable contact 11 which contact / separate to the neutral contact 16 side are the same edge parts.

  FIG. 5 shows a perspective view of the movable contacts 10 and 11. 5A is a perspective view of the movable contacts 10 and 11, FIG. 5B is a perspective view of a cross section of the movable contacts 10 and 11, and FIG. 5C is a perspective view of the contact 20 of the movable contacts 10 and 11. is there. The movable contacts 10 and 11 are provided with a holder 19, a contact 20, an elastic body 21, a spacing tube 22, fastening members 23a and 23b, a contact plate 24, bearings 25a to 25d, and an engagement shaft 26, respectively.

  The holder 19 and the contact 20 are arranged to face each other. The holder 19 is installed close to the switching shaft 9, and the contact 20 is held by the holder 19 from the inside of the switching switch. The contact 20 is a member that makes contact with the neutral contact 16 that is a fixed contact and the tap contact 17 or 18 to create a short circuit state. The contacts 20 are arranged in five layers in the vertical direction. At the left and right end portions of each contact 20, contact portions 20 c are formed that protrude in the direction opposite to the holder 19, that is, in the outward direction of the switching switch. Each contact 20 is provided with through holes 20a and 20b inside the contact portion 20c. The through hole 20a is formed in a circular shape, and the through hole 20b is formed as a horizontally long slot.

  The elastic body 21 is installed between the contact 20 and the holder 19 so as to be stretchable. The elastic body 21 is biased so as to press the contact 20 against the contact plate 24. The spacing tube 22 is attached to the through holes 20 a and 20 b of the contact 20 between the contact plate 24 and the holder 19. The fastening members 23a and 23b are members for fixing the contact plate 24 and the holder 19 via the spacing tube 22, and the contact plate 24 is a member for positioning the contact 20 at a predetermined position.

  The bearings 25 a and 25 b are fixed to the upper part of the holder 19, and the bearings 25 c and 25 d are fixed to the lower part of the holder 19. The bearings 25 a, 25 b and 25 c, 25 d are arranged in a pair along the same direction as the elastic body 21. The engaging shaft 26 is provided at the vertical center position in the horizontal direction of the holder 19 so as to protrude downward from the height center position.

  However, as already described, since the first movable contact 10 and the second movable contact 11 are arranged upside down, if the protruding direction of the engagement shaft 26 of the first movable contact 10 is defined as the lower side, 2 The protruding direction of the engagement shaft 26 of the movable contact 11 is defined as upward. The engagement shaft 26 is fitted in the cam grooves of the cam disks 12 and 13.

  In the state shown in FIG. 4, the engagement shaft 26 of the second movable contact 11 protruding downward is fitted in the cam grooves 13 a to 13 c. Although not shown, the engagement shaft 26 of the first movable contact 10 protrudes upward and is fitted into the cam groove of the cam disk 12. Since the engaging shafts 26 of the movable contacts 10 and 11 are fitted in the cam grooves of the cam disks 12 and 13 as described above, when the cam disks 12 and 13 are rotated by the rotation of the switching shaft 9, the engaging shafts 26 and 11 are engaged. The shaft 26 slides along the cam groove, and the movable contacts 10 and 11 operate in the radial direction.

  As shown in FIG. 6, the guide plate 14 is formed with six guide holes 14 a to 14 f extending radially from the center of the switching shaft 9. Around each guide hole 14a-14f, the wide groove part 141 is provided so that it may be enclosed. Bearings 25a and 25b or 25c and 25d of the movable contacts 10 and 11 are engaged with the guide holes 14a to 14f, and the operation direction of the movable contacts 10 and 11 is defined.

  A substantially cross-shaped guide member 27 is attached to the bearings 25a, 25b or 25c, 25d engaged with the guide holes 14a to 14f, and the guide member 27 is slidably fitted into the groove portion 141. Although not shown, six guide holes are also formed radially from the center of the switching shaft 9 on the lower surface of the guide plate 15. The bearings 25a, 25b or 25c, 25d below the movable contacts 10, 11 are also engaged with these guide holes, and the operation direction of the movable contacts 10, 11 is defined.

(2) Operation of movable contact In the present embodiment having the above-described configuration, when the switching shaft 9 is rotated by torque from an accumulating mechanism (not shown), the first cam disk 12 and The second cam disk 13 rotates, and the engagement shaft 26 (shown in FIG. 5) of the movable contacts 10 and 11 slides along the cam groove (13a to 13c in FIG. 4). , 11 operate in the radial direction.

  As for the 1st movable contact 10 and the 2nd movable contact 11 which move along the cam groove of the cam discs 12 and 13, the moving direction and guide position of a radial direction are antiphase. Therefore, when the first movable contact 10 moves outward in the radial direction, the contact 20 of the first movable contact 10 contacts the neutral contact 16 and the first tap contact 17. At the same time, the second movable contact 11 moves inward in the radial direction, and the contact 20 is separated from the neutral contact 16 and the second tap contact 18.

  On the contrary, when the first movable contact 10 moves inward in the radial direction, the contact 20 of the first movable contact 10 moves away from the neutral contact 16 and the first tap contact 17. At the same time, the second movable contact 11 moves outward in the radial direction, and the contact 20 contacts the neutral contact 16 and the second tap contact 18. Thus, in this embodiment, since the two movable contacts 10 and 11 operate in the opposite phase in the radial direction as the switching shaft 9 rotates, the movable contacts 10 and 11 move in the opposite directions to each other. The short circuit connection between the sexual contact 16 and the two tap contacts 17 and 18 is switched.

(3) Effects According to the present embodiment as described above, the neutral contact 16 is not always in contact with the movable contacts 10 and 11, and therefore the neutral contact 16 does not frequently repeat the sliding operation. Contact wear is reduced. Therefore, the switching switch can ensure a desired contact resistance over a long period of time and can reliably suppress an excessive temperature rise. Therefore, the switching switch and the on-load tap switching device using the same can obtain excellent durability.

  Further, in the present embodiment, there is no link lever that transmits torque from the switching shaft 9 to the movable contacts 10 and 11 as in the prior art, and the amount of displacement in the radial direction of the cam groove formed in the cam plates 12 and 13 and the movable amount are movable. The amount of movement of the contacts 10 and 11 is equal. Therefore, the amount of movement of the movable contacts 10 and 11 is hardly affected by the dimensions of the members and assembly errors, and the movable contacts 10 and 11 can be positioned with high accuracy by the rotation of the cam disks 12 and 13.

  In addition, in the present embodiment, the two through holes 20a of the contacts 20 of the movable contacts 10 and 11 are formed in a circular shape and the through hole 20b is formed in a long hole. Even when the contact positions with the contact points 17 and 18 vary, the elongated hole portion of the through hole 20b cancels the variation. Thereby, the movable contacts 10 and 11 can be short-circuit joined to the neutral contact 16 and the tap contacts 17 and 18.

  Further, since the neutral contacts 16 and the tap contacts 17 and 18 are all arranged on the same circumference and in the middle of the tap contacts 17 and 18, a total of nine fixed contacts can be equally efficiently distributed. Can be arranged. Therefore, it is possible to reduce the size of the switching switch. Furthermore, the neutral contact 16 of the present embodiment integrally constitutes a contact connected to the first tap contact 17 and a contact connected to the second tap contact 18. Moreover, in the present embodiment, the two movable contacts 10 and 11 are arranged by arranging the two cam disks 12 and 13 formed in the same shape on the switching shaft 9 so that the surfaces on which the cam grooves are formed face each other. Can be operated in antiphase.

  In addition to these configurations, the link lever is also omitted in this embodiment as described above. Therefore, the switching switch can reduce the space occupied by the constituent members, and can also simplify the configuration. Therefore, not only can the switching switch be downsized, but it is also possible to provide inexpensive equipment by sharing parts.

  Furthermore, in the movable contacts 10 and 11 of the present embodiment, the contact 20 is held inside the movable contacts 10 and 11 by the holder 19. Therefore, the movable contacts 10 and 11 can be configured compactly, which is effective for downsizing. In the present embodiment, the two movable contacts 10 and 11 are turned upside down and applied to the energization switching mechanism. Therefore, it can be used in common as a pair of movable contacts 10 and 11 for switching the power supply, and it is possible to configure a power supply switching mechanism at a low cost.

  In the present embodiment, the two tap contacts 17 and 18 are fixed along the inner diameter surface of the insulating cylinder 28, and one end of the fixed portion is a junction contact of the movable contact mechanism 29 for switching the tap potential. Therefore, the tap contacts 17 and 18 can be used as the support column of the energization switching mechanism portion, and a switching switch having excellent rigidity can be provided. Furthermore, in this embodiment, the movable contact mechanism 29 for switching the tap potential can be provided inside the insulating cylinder 28, which can contribute to downsizing of the device.

(4) Other Embodiments The above-described embodiment is presented as an example in the present specification, and is not intended to limit the scope of the invention. In other words, the present invention can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the invention described in the claims and equivalents thereof in the same manner as included in the scope and gist of the invention.

DESCRIPTION OF SYMBOLS 9 ... Switching shaft 10 ... 1st movable contact 11 ... 2nd movable contact 12 ... 1st cam disc 13 ... 2nd cam discs 14, 15 ... Guide plates 14a-14f ... Guide hole 16 ... Neutral contact 17 ... First 1 tap contact 18 ... 2nd tap contact 19 ... holder 20 ... contacts 20a and 20b ... through hole 21 ... elastic body 22 ... spacing tube 23a and 23b ... fastening member 24 ... contact plate 25a to 25d ... bearing 26 ... engagement shaft 27 ... Guide member 28 ... Insulating cylinder 29 ... Tap potential switching contact mechanism

Claims (7)

A first tap contact having a first tap potential;
A second tap contact having a second tap potential;
At least one neutral contact having a neutral potential;
A first movable contact detachable from the first tap contact and the neutral contact;
A second movable contact detachable from the second tap contact and the neutral contact;
A rotatable switching shaft,
A first cam plate fixed to the switching shaft and operating the first movable contact;
A switching switch, comprising: a second cam plate fixed to the switching shaft and operating the second movable contact.   The first tap contact, the second tap contact, and the neutral contact are disposed on the same circumference, and the neutral contact is disposed between the first tap contact and the second tap contact. The switching switch according to claim 1.   The switching opening / closing according to claim 1 or 2, wherein the neutral contact connected to the first tap contact and the neutral contact connected to the second tap contact are configured as one component. vessel. The first movable contact and the second movable contact are installed in an inverted state,
A cam groove having the same shape is formed on the first cam plate and the second cam plate and arranged opposite to each other,
The first movable contact is engaged with the cam groove of the first cam, and the second movable contact is engaged with the cam groove of the second cam. The switching switch according to item 1. Providing an insulating cylinder for fixing the first tap contact, the second tap contact and the neutral contact;
A movable contact mechanism is arranged inside the insulating cylinder,
The said 1st tap contact, the said 2nd tap contact, and the said neutral contact are extended and formed in the axial direction of the said insulation cylinder, and comprise a part of said movable contact mechanism. The switching switch according to any one of 4.   6. The movable contact according to any one of claims 1 to 5, wherein the movable contact has a contact having two through holes, and at least one of the through holes is a long hole. Switching switch as described.   7. A load tap switching device using the switching switch according to any one of claims 1 to 6.

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